Tire Size Box

275/80R16 vs 275/85R16

275/85R16 compared with 275/80R16

+3.2% diameter, 0.0" width

275/85R16 is 34.41" tall vs 33.32". More than the 3% rule of thumb, so check carefully before switching.

33.3"16" rim8.7"10.8" wide
275/80R16 (solid) compared with 275/85R16 (dashed outline), drawn to scale

With 275/85R16 tires, when your speedometer says 60 mph you are really going

61.9 mph

275/85R16 is +1.08 inches (+3.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/80R16275/85R16Difference%
Overall diameter33.32"34.41"+1.08"+3.2%
Section width10.83"10.83"0.00"0.0%
Sidewall height8.66"9.20"+0.54"+6.3%
Circumference104.69"108.09"+3.40"+3.2%
Revolutions per mile605.2586.2−19.0−3.1%

Speedometer difference

If your vehicle came with 275/80R16 and you fit 275/85R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph31.0 mph+1.0 mph
40 mph41.3 mph+1.3 mph
50 mph51.6 mph+1.6 mph
60 mph61.9 mph+1.9 mph
65 mph67.1 mph+2.1 mph
70 mph72.3 mph+2.3 mph
75 mph77.4 mph+2.4 mph
80 mph82.6 mph+2.6 mph

Each size on its own

Questions

Which is bigger, 275/80R16 or 275/85R16?
275/85R16 is taller by 1.08 inches (34.41" vs 33.32"). 275/80R16 is the same width.
Can I replace 275/80R16 with 275/85R16?
It is not recommended without checking carefully. The diameter difference is +3.2%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 275/85R16 change my speedometer?
When your speedometer reads 60 mph with 275/85R16 fitted (calibrated for 275/80R16), your real speed is 61.9 mph. Your odometer will under-count miles by about 3.2%.
Will 275/85R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.54 inches of ground clearance at the axle.

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